Main Menu. 17.5 The Wittig and Related Reactions. The Wittig Reaction (formation of alkenes). General Reaction:. R´ and R” can be H or alkyl group. Phosphine oxide. Wittig reagent (a phosphonium ylide ). General Reaction:. base. Formation of Wittig Reagents. A phosphonium salt.
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17.5 The Wittig and Related Reactions
The Wittig Reaction
(formation of alkenes)
R´ and R” can be H or alkyl group.
Wittig reagent (a phosphoniumylide)
Formation of Wittig Reagents
A phosphonium salt
Mechanism of Wittig Reaction
Examples of Wittig Reaction
Wittig reagents favor the Z (cis) isomer.
Horner-Emmons reaction (general reaction):
Reactions of Aldehydes and Ketones with Horner-Emmons Reagent
R = Et (most common)
Arbuzov (Perkow) reaction:
Formation of Horner-Emmons Reagent
R = alkyl, acyl or R’OC(O)-
Mechanism of Horner-Emmons Reaction
Examples of Horner-Emmons Reaction
Horner-Emmons reagents favor the E (trans) isomer.
1. What could be the reagent for the following transformation?
2. What should be the product from the following reaction?
3. What could be the product for the following reaction?